"Really Don't Care" is an uptempo dance-pop song, with influences of bubblegum pop,[3] that runs for three minutes and twenty-one seconds.

Lyrically, the song is a message of defiance to a former lover, with Lovato confidently singing such lines as, "Even if the stars and moon collide, I never want you back into my life.

"[4] The song is set in the key of G major and maintains a moderately fast tempo of 121 beats per minute in common time.

"[6] Billboard writer Jason Lipshutz praised Lovato's "sassy" confidence on the track, which effectively showcases her "overpowering pipes".

[8] On the other hand, Melinda Newman of HitFix found the song to be too generic, comparing it to Icona Pop's breakout hit "I Love It" (2012).

The video was filmed on June 8, 2014 at the LA Pride Parade and features cameo appearances from Perez Hilton, Kat Graham, Shane Bitney Crone, Bria Kam and Chrissy Chambers,[13] John Taylor, Travis Barker and Wilmer Valderrama.

Once released in May 2014, performances include on the Season 13 Live Final of American Idol,[17] Good Morning America Summer Concert Series, Late Night with Seth Meyers, and the 2014 Teen Choice Awards.